Illumination devices that are referred to as so-called desk lights are in general use (e.g., see Patent Literatures 1 to 3). With such illumination devices, a user moves the device as appropriate to adjust its position such that the desired position of the desk is provided with appropriate illuminance.
Various improvements have been made to such desk lights, and an illumination device in which motors are provided in movable portions that are for changing the illumination direction is known (e.g., see Patent Literature 1). Also, an illumination device that adjusts the color and controls the irradiation range to deal with the case where the focus adjustment function of the eyes declines with factors such as age and fatigue is known (e.g., see Patent Literature 2). Furthermore, an illumination device that adjusts the light after determining character size and whether the object being illuminated is color or monochrome is known (e.g., see Patent Literature 3).